Werbung
)F
1
MKII
E
i
n
stel
lu
ngen /
Adju
stm
ents
Adjustments
Itleasuring
instruments/equipment:
:requency
counter,
AF-voltmeter,
DC-voltmeter, AF-generator,
distortion
analyzer, wow and
flutter
meter,
)r
test
cassette 448
A
(par1
no. 35079-023.00), torque test cassette
456
(part no. 35079-014.00).
[ayout
of adiustment
controls
see page
2-3.
The symbol
O
refers
to
a
test point
in
the circuit diagram.
Adjustment
Preparaiions
Adjustment Procedure
1. Tape speed
Frequency counter
to
LINE OUT.
lnsert the test cassette 448
A,
play
3150
Hz.
With
adiustment
control
R
535
(Logic board)
set
the
f
requency
to 3150
Hz
t
0,1
o/".
2.
Take-up
torque
on
Start
Load
the
torque test cassette
456
(Deck A/B).
Function:
Start.
On
START,
the torque should
be 25
1o70
x
104 Nm
= 40
g-cm.
3.
Wow and
flutter
Wow and
flutter
meter to
LINE OUT.
Load
test cassette 448 A
(Deck A/B).
Play back
31
50
Hz.
Deviation <
0.13o/o
(lEC
wtd.).
Playback
measuring
time
> 30 seconds.
4.
MPX-filter
(1
9 kHz stereo
pilot tone)
Connect
the AF-generator
(f1=
315
Hz,
fr=
19
kHz,
ca.
1
15 mV) to
the LINE lN
sockets.
Connecl the
AF-voltmeter
to
the
test points
O
Dl
(lett
channel)
or
O
D2
(right channel).
Function: Record-Pause, Dolby
off,
balance
control
to'mid-position".
Set
the
level control (RECORD LEVEL)
during
Record-
Pause so
that
at
315
Hz the
voltage
measured at the
test
points
(.,r
DI
and
O
D2
is
V"
=
388 mV
(=
0
dB).
At
1
I
kHz
=
V.
<
12 mV
(<
-30
dB).
Adlust with
F101
(left channel) or
F
102
(right channel).
5.
Erase
frequency
Connect
the
frequency counter
to
O
TP L 1
(R 253).
lnsert a recordable cassette,
Cr
tape (lEC ll).
Function:
Record-Start.
The oscillator frequency should
be
85 kHz +
10
kHz
.
Adjust with L
103.
6.
Erase
current
Connect the
AF-voltmeter
to
O
TP L 1
(in parallel
with
R 253)
lnsert a recordable cassette with
Cr
tape (lEC
ll).
Function:
Record-Start.
Erase
current:
100
mA +
10%
measured at
R
253
=
100
mV + 10%.
7.
HX-PRO
Connectthe
Dc-voltmeterto
Pin
13
lC'105
(rightchannel)
or
to Pin 6 lC 105
(left
channel).
lnsert a recordable cassette with
Cr
tape (lEC
ll).
Function:
Record-Star1, Dolby off,
Adjust
for minimum
DC
voltage
with
L
104
at pin
13
lC
105 (right
channel)
and
with L
105 at
pin
6
lC
105 (left
channel).
8.
Record
blocking
circuits
(bias filter)
Connect the
AF-voltmeter
to
test point L)
D3 (left
channel)
or to test point
Lr
D4 (right channel) on the audio circuit
board.
lnsert a recordable cassette with
Cr
tape (lEC
ll).
Function: Record-Start, Level
pot. closed.
Adjust
for
minimum
RF
with
F
106
at
test
point
O
D3 (left
channel) and
F 105 at
test
point
O
D4
(right channel).
9.
Playback level
Reference tape
scanning
(Dolby level)
Connect the
AF-voltmeter
to
test point
O
D1 (left
channel)
or
test point
O
D2
(right channel)
on
the audio circuit board.
Load the
test cassette 448
A.
Play back
315
Hz
(250
nWb/m).
Dolby
of{.
Set
the playback
level
with the adjustment control
R
't56
(left channel)
or
R
157 (right channel) to
490
mV
+0.5
dB
(LINE OUT =
950
mV).
When using
a
test
cassette
with 200
nWb/m
set
the
playback level to 388 mV
+
0.5
dB
(LINE OUT
=
750 mV).
1O.Head
gap angle
(Azimuth)
Connect
AF-voltmeter
to
LINE
OUT
L (left channel) or to
LINE
OUT
R (right channel).
Load
the test cassette 448 A, play back
10 kHz.
The adjustment
hole for
the
head
adjustment screw 81
is
accessible by removing the cassette compartment Iid
19
(with
open cassette compartment
push the
cover upwards).
With
the
head adjustment screw
81
set
the
left
or
right
channel
to
maximum
level.
Then
connect
the Ieit
channel
in
parallel
with
the
right
channel.
By
minimum re-adjustment
of
the
head
adjustment
screw
81
set the output
level
to maximum.
)
RU N
DIG Servicetechnik
2-4
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